Sole with buffer elements

ABSTRACT

A sole is provided with a plurality of buffer elements embedded in the sole at areas bearing most part of pressure applied to the sole by a wearer&#39; foot. Each of the buffer elements includes a non-magnetic housing having a compressible structure, and two permanent magnets vertically oppositely disposed in the housing. Inner sides of the two permanent magnets have the same polarity to produce a magnetic repulsive force between the two magnets to normally expand the compressible housing to its maximum volume. When the housing is subjected to an external pressure, the magnetic repulsive force between the two magnets supports the housing while allowing the same to elastically deform and absorb a reactive force from the ground, so that a buffer effect is obtained.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a sole with buffer elements, andmore particularly to a sole having buffer elements embedded therein atareas bearing most part of pressure applied to the sole, so that abuffer effect is provided by the sole to protect a wearer's bones andjoints at foot and knee against undesired impact and injury duringexercises and/or sporting activities.

[0002] To protect wearers from injured feet, ankles, and knees duringexercises and/or sporting activities, shoe manufacturers have developedsoles made of materials with enhanced elasticity. The elastic soles arecompressively deformed to absorb a reactive force from the ground whenthe wearers jump and contact at feet with the ground again, andtherefore reduce the impact on the wearers' feet and joints to avoidathletic injuries.

[0003] Another type of air-cushioned shoe has also been developed toincrease the vibration-absorbing ability of the sole. The air-cushionedshoe includes a sole provided with a flat air cushion that is an airchamber in the sole and filled with air. When the air cushion issubjected to an external pressure, the internal air, due to its inherentcompressibility, will absorb a part of the reactive force from theground to reduce the impact on a wearer's foot. Since the volume of airincreases with rising temperature, the air cushion is largely affectedby the temperature in its structural strength and elastic performance.When the temperature rises, air pressure inside the air cushionincreases to relatively reduce the limit value of pressure bearable bythe air cushion. That is, it is possible an air cushion in use breaksdue to an overly high internal air pressure thereof when the temperaturerises. On the other hand, when the temperature significantly lowers, theair cushion will have a largely decreased internal air pressure andaccordingly reduced elastic performance and buffer effect.

SUMMARY OF THE INVENTION

[0004] A primary object of the present invention is to provide a solehaving buffer elements embedded therein. The buffer element of thepresent invention has preset structural strength and elastic performancethat can be maintained even the sole has been used over a long period oftime. The buffer element provides the sole with a highly stable buffercapacity to minimize athletic injuries possibly caused by undesiredvibration of and impact on foot.

[0005] The buffer element of the present invention includes anon-magnetic housing and two permanent magnets vertically oppositelydisposed in the housing. Inner sides of the two magnets facing towardeach other have the same magnetic polarity to produce a magneticrepulsive force between the two magnets. The housing is formed from twoparts that are vertically movably connected together through engagementof retaining means with long slots separately correspondingly providedon the two parts. When the housing is subjected to an external pressure,the two parts vertical move relative to each other for the housing tocompressively deform within a predetermined extent.

[0006] The compressively deformable housing is normally expanded to itsmaximum volume by the magnetic repulsive force between the two magnetsvertically oppositely disposed in the housing. When the housing issubjected to an external pressure, the magnetic repulsive force supportsthe housing while allowing the same to compressively deform and absorb areactive force from the ground. A buffer effect can therefore beachieved.

[0007] In another embodiment of the present invention, the two permanentmagnets are attached at outer sides to two identical magnetic seats inthe form of a shallow plate having an annular peripheral wall definingan open top. The two magnetic seats are oriented for their open tops toface toward each other. End surfaces of the annular peripheral walls ofthe two magnetic seats are induced magnetic poles having a polarityreverse to that of the inner sides of the two magnets, so that amagnetic circuit is formed in the housing to provide an increasedmagnetic repulsive force between the two magnets.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The structure and the technical means adopted by the presentinvention to achieve the above and other objects can be best understoodby referring to the following detailed description of the preferredembodiments and the accompanying drawings, wherein

[0009]FIG. 1 is a top view of a sole with buffer elements according tothe present invention;

[0010]FIG. 2 is an assembled perspective view of a first embodiment ofthe buffer element of the present invention;

[0011]FIG. 3 is an exploded perspective view of the buffer element ofFIG. 2;

[0012]FIG. 4 is a sectional view taken along line 4-4 of FIG. 1;

[0013]FIG. 5 is an exploded perspective view of a second embodiment ofthe buffer element of the present invention; and

[0014]FIG. 6 is a cross sectional view of the buffer element shown inFIG. 5.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Please refer to FIG. 1 that is a top view of a sole 10 accordingto the present invention. As shown, the sole 10 is provided with aplurality of buffer elements 20 that are separately embedded in the sole10 at areas bearing most part of pressure applied to the sole 10, suchas a front portion below a wearer's ball of foot, and a rear portionbelow the wearer's heel.

[0016] Please refer to FIGS. 2 and 3 that are assembled and explodedperspective views, respectively, of a first embodiment of the bufferelement 20, and to FIG. 4 that is a cross sectional view taken alongline 4-4 of FIG. 1. The buffer element 20 includes a housing 21 made ofa non-magnetic material, and two permanent magnets 22, 23 disposed inthe housing 21. The two permanent magnets 22, 23 are verticallyoppositely disposed in the housing 21 with two sides having the samemagnetic polarity facing toward each other, so that the two permanentmagnets 22, 23 are always pushed away from each other by a magneticrepulsive force. The housing 21 has a compressible structure and isnormally expanded to its maximum volume by the magnetic repulsive forcebetween the two permanent magnets 22, 23. When the housing 21 issubjected to an external pressure, the magnetic repulsive force betweenthe two permanent magnets 22, 23 serves as a support to the housing 21while allowing the housing 21 to compressively deform under the pressureand absorb a reactive force from the ground. A buffer effect istherefore achieved.

[0017] The housing 21 may be formed from two vertically connected parts,namely, an upper and a lower part 21 a, 21 b. The upper part 21 a of thehousing 21 is provided at predetermined positions with a plurality ofradially projected retainers 21 c, and the lower part 21 b of thehousing 21 is provided with a plurality of vertically extended longslots 21 d corresponding to the retainers 21 c, so that the retainers 21c are upward and downward movably received in the long slots 21 d whenthe two parts 21 a, 21 b are connected to each other. When the housing21 is subjected to an external pressure, the upper and the lower parts21 a, 21 b can vertically move relative to each other, allowing thehousing 21 to be compressed by a certain extent. When the externalpressure no longer exists, the magnetic repulsive force between the twomagnets 22, 23 expands the housing 21 to its maximum volume again.

[0018] In designing the buffer element 20, the physical principle ofrepulsion between two magnetic poles having the same polarity isemployed to provide the buffer element 20 with a predetermined extent ofelasticity. Since the magnets 22, 23 can be easily manufactured underprecise control to produce a desired magnetic strength, it is possibleto precisely set the buffer element 20 to a desired buffer capacity thatwould not decrease even the buffer element 20 has been used over a longtime. That is, even the sole 10 has been used over a period of time, itwill have a buffer capacity the same as that it has in a completely newcondition. This is an advantage of the present invention superior to theconventional air-cushioned shoes.

[0019] The buffer element 20 embedded in the sole 10 at an area close tothe wearer's heel is usually provided with increased buffer capacity tocreate better vibration-absorbing effect. Moreover, it is preferable toembed more than one buffer element 20 in the sole 10 at an area close tothe wearer's ball of foot to evenly support the wearer's sole.

[0020] It is preferable for the magnets 22, 23 to have a magneticstrength not strong enough to reach beyond an outer side of the sole 10to attract magnetic substances on the ground. Normally, the magneticstrength designed for the magnets 22, 23 is one that can be wellisolated from the ground by the housing 21 and the sole 10.

[0021]FIGS. 5 and 6 are exploded perspective and assembled crosssectional views, respectively, of a second embodiment of the bufferelement 20 of the present invention. In this second embodiment, thepermanent magnets 22, 23 are also vertically oppositely disposed in twoparts 21 a, 21 b of the housing 21 but with their outer sides that faceaway from each other attached to magnetic seats 30, 31, respectively.The magnetic seats 30, 31 are identical members and are in the form of ashallow plate having an annular peripheral wall defining an open top ofthe seats 30, 31. The magnetic seats 30, 31 are located behind themagnets 22, 23 with the open tops facing toward each other. End surfaces30 a, 31 a of the annular peripheral walls of the magnetic seats 30, 31are induced magnetic poles having a polarity reverse to that of theinner sides of the magnets 22, 23, so that a magnetic circuit is formedin the housing 21 to increase the repulsive force between the twopermanent magnets 22, 23. More specifically, when the inner sides of themagnets 22, 23 are, for example, S poles, the end surfaces 30 a, 31 a ofthe annular peripheral walls of the two seats 30, 31 are induced Npoles. By providing the two plate-shaped magnetic seats 30, 31, thebuffer element 20 may have increased elastic strength. However, it is tobe noted that the induced magnetic poles of the magnetic seats 30, 31are located at the end surfaces 30 a, 31 a of their annular peripheralwalls, and there is not any magnetic field line at outer sides 30 b, 31b of the magnetic seats 30, 31. That is, the buffer element 20 with themagnetic seats 30, 31 would absolutely not attract magnetic substanceson the ground.

[0022] In brief, the sole with buffer elements according to the presentinvention has the advantages of being structural strong and highlydurable, and can be easily constructed to have any desired buffercapacity.

What is claimed is:
 1. A sole with buffer elements, comprising a soleand a plurality of buffer elements embedded in said sole at areas thatbear most part of pressure applied by a wearer's foot to said sole; eachof said buffer elements including a housing made of a non-magneticmaterial and having a compressible structure, and two permanent magnetsvertically oppositely disposed in said housing with two sides having thesame magnetic polarity facing toward each other to produce a magneticrepulsive force between said two permanent magnets; and said housingbeing normally expanded by said magnetic repulsive force to a maximumvolume thereof.
 2. The sole with buffer elements as claimed in claim 1,wherein said housing is formed from two vertically connected parts, afirst one of which being provided at predetermined positions with aplurality of radially projected retaining means, and a second one ofwhich being provided with a plurality of vertically extended long slotscorresponding to said retaining means, such that said retaining meansare upward and downward movably received in said long slots.
 3. The solewith buffer elements as claimed in claim 1, wherein said two permanentmagnets are respectively attached at outer sides to two magnetic seats,said two magnetic seats being identical to each other and in the form ofa shallow plate having an annular peripheral wall defining an open topfor each said magnetic seat, and said two magnetic seats being orientedwith said open tops facing toward each other.